Performance of a residential heat pump operating in the cooling mode with single faults imposed

Sensitivity Analysis of Installation Faults on Heat Pump Performance

“…SCE single-fault tests at a low refrigerant charge showed similar degradations in cooling capacity and total power as Kim et al (2006); SCE reported -3 % and 0 % change in cooling capacity and total power, respectively, at 13 % undercharge while Kim et al (2006) reported -5 % and -2 % change at 10 % refrigerant undercharge. However, at higher fault levels, SCE measured much higher performance degradation than Kim et al; cooling capacity and total power changed by -54 % and -5 %, respectively, at 27 % undercharge (SCE) compared to -17 % and -3 % at 30 % undercharge (Kim et al, 2006). These large differences in cooling capacity change for a similar fault level exemplify differences in the effect a given fault may have on different systems.…”

“…Reports of major studies on FDD for HVAC systems started to appear in the literature in the nineties, and the number of publications noticeably increased in the last fifteen years. Kim et al (2006) and Payne et al (2009) present detailed literature reviews up to the dates these reports were published and include laboratory data for the cooling and heating mode, respectively. These laboratory data are used in our report; however, they had to be extended through tests in environmental chambers to provide complete coverage of the whole range of installation faults of interest in this study (see chapter 3 of this report).…”

“…Tables 3.1 presents the cooling and heating test conditions (indoor dry bulb, indoor dew point, and outdoor dry bulb temperatures), and Table 3.2 presents the measurement uncertainties. For the uncertainty analysis and detailed description of the experimental setup the reader should refer to Kim et al (2006). Table 3.3 lists seven studied faults, including their definition and range.…”

“…These laboratory data are used in our report; however, they had to be extended through tests in environmental chambers to provide complete coverage of the whole range of installation faults of interest in this study (see chapter 3 of this report). Comstock and Braun (2001) Centrifugal chiller Experiment, eight single faults Kim et al (2006Kim et al ( , 2009 Split residential heat pump Experiment for cooling mode, single-faults Chen and Braun (2001) Rooftop air conditioner Simplified rule-based chart method Navarro- Esbri et al (2007) General vapor compression system Dynamic model based FDD for real-time application Payne et al (2009) Single-speed, split residential heat pump Experiment for heating model, single-faults Wang et al (2010) HVAC system for new commercial buildings System-level FDD involving sensor faults Cho et al (2005) Air-handling unit for buildings Multiple faults Li and Braun (2007) Direct expansion vapor compression system Multiple faults Du and Jin (2008) Air handling unit Multiple faults Southern California Edison Design and Engineering Services (SCE 2012) Single-speed, split residential air conditioner Single faults, dual faults, and triple faults A large number of laboratory cooling mode tests were performed by Southern California Edison (SCE 2012) to determine the effects of common faults on air conditioner performance. These faults included indoor airflow, outdoor airflow, refrigerant charge, non-condensables, and liquid line restrictions.…”

“…A significant number of laboratory tests were taken by Kim et al (2006) and Payne et al (2009) to characterize heat pump performance degradation due to faults. For the purpose of this study, we conducted additional tests using the same heat pump and test apparatus to expand the ranges of previously studied faults and to include faults that were not covered earlier, specifically, improper electric line voltage and improper liquid line subcooling.…”